Pressure accumulators are known in various embodiments in the prior art. For example, DE 20 2007 008 175 U1 discloses a hydropneumatic pressure accumulator or hydraulic accumulator having a movable separation element disposed in an accumulator housing. The separation element separates a first working space, preferably a gas space, from a fluid space, as the second working space, and is formed by a diaphragm of a flexible material, in particular an elastomer. At least one housing opening, forming an access to the housing, is provided on the accumulator housing for accommodating and dispensing fluid, in particular in the form of hydraulic fluid.
Pressure accumulators of this type, in particular hydraulic accumulators, are subjected to high demands during operation in hydraulic systems because frequent and intense movements of the elastomeric separation element occur in predefinable operating cycles due to the fluid flowing into and out of the accumulator. This operation causes loading and relaxation separately by the separation element with respect to the gas supply in the accumulator. Overloading and local wrinkling of the material may then occur due to shearing stresses on the separation element and may result in tearing. Tearing would fundamentally make the accumulator useless and would require the hydraulic system to be shut down, at least partially, for replacement purposes. The known pressure accumulators and hydraulic accumulators can be used regularly only as an individual solution for a restricted range of applications in hydraulic systems because of their accumulator capacity and/or their damping characteristics. This restriction leads to a corresponding increase in costs at both the manufacturing end and the consumer end.
DE 197 43 007 A1 describes an accumulator of the pressure accumulator type, having a housing with a connection for a pressure medium in the manner of a hydraulic medium that can be stored in the housing. The housing contains a filling agent in the form of one or more hollow bodies filled with a pressure medium that can be compressed when a higher pressure prevails outside of the filling agent.
DE 695 15 899 T2 relates to an energy accumulator, among other things, formed from a rigid outer casing of two parts clamping a separation diaphragm. A heterogeneous structure for accumulation or dissipation of energy, having a capillary porous solid matrix surrounded by a lyophobic liquid, is provided in a compartment of the energy accumulator bordered by the separation diaphragm. The compartment is isolated from any contact with another hydraulic fluid.